PHP 使用MySQLi的方式操作MySQL数据库

创建数据库，创建数据表，插入数据。

connect_error) {
		die("连接失败: " . $mysql->connect_error);
	} 
	echo "连接数据库成功"."
";
	//判断是否存在database,如果不存在才继续创建
	$result = $mysql->query("show databases like 'myDb'");
	if ($result->fetch_all()[0][0] == "myDb"){
		die( "数据库已存在"."
");
	}	
	// 创建数据库
	$sql = "CREATE DATABASE myDb";
	if ($mysql->query($sql) === TRUE) {
		echo "数据库创建成功"."
";
	} else {
		die("数据库创建失败: " . $mysql->error);
	}	
	$mysql->select_db("myDb");
	$sql = "CREATE TABLE myTable(
			inputId INT(11) UNSIGNED AUTO_INCREMENT PRIMARY KEY, 
			userName VARCHAR(50) NOT NULL,
			passWord VARCHAR(255) NOT NULL,
			nickname VARCHAR(50),
			logTimes INT(11) NOT NULL DEFAULT 0,	
			lastLoginTime TIMESTAMP DEFAULT CURRENT_TIMESTAMP ON UPDATE CURRENT_TIMESTAMP,
			reg_date TIMESTAMP DEFAULT CURRENT_TIMESTAMP
	)";
	if ($mysql->query($sql) === TRUE) {
		echo "数据表创建成功";
	} else {
		die( "创建数据表失败: " . $mysql->error);
	}
	$sql = "INSERT INTO myTable(userName, passWord, nickname)
			VALUES ('admin', '".sha1("admin")."', 'admin')";
	if ($mysql->query($sql) === TRUE) {
		echo "数据写入成功"."
";
	} else {
		die( "数据写入错误: " . $mysql->error);
	}	
?>

使用phpmyadmin验证结果正确。

 

读取数据，查找数据

// 创建连接
$mysql = new mysqli($servername, $username, $password,$dbname);

// 检测连接
if ($mysql->connect_error) {
	die("连接失败: " . $mysql->connect_error);
} 
echo "连接数据库成功"."
";

// 读取数据库
$result = $mysql->query("SELECT inputId, userName, nickName FROM userauthentication");

if ($result->num_rows > 0) {
	// 输出数据
	while($row = $result->fetch_assoc()) {
		echo "id: " . $row["inputId"]. " - Name: " . $row["userName"]. " " . $row["nickName"]. "
";
	}
} else {
	echo "0 结果";
}

//使用where选择读取数据库
echo "使用where查找“admin”". "
";
$result = $mysql->query("SELECT * FROM userauthentication WHERE userName='admin'");
if ($result->num_rows > 0) {
	// 输出数据
	while($row = $result->fetch_assoc()) {
		echo "id: " . $row["inputId"]. " - Name: " . $row["userName"]. " " . $row["nickName"]. "
";
	}
} else {
	echo "0 结果";
}
echo "使用where查找“guest”". "
";
$result = $mysql->query("SELECT * FROM userauthentication WHERE userName='guets'");
if ($result->num_rows > 0) {
	// 输出数据
	while($row = $result->fetch_assoc()) {
		echo "id: " . $row["inputId"]. " - Name: " . $row["userName"]. " " . $row["nickName"]. "
";
	}
} else {
	echo "0 结果";
}

$mysql->close();

运行读取结果，因为没有插入“guest”数据，所以查找“guest”提示0结果。